This invention relates to an apparatus for cleaning the bristle bed of a sheet material cutting machine to remove loose fibers, threads, small pieces of work material and other debris which tend to collect in the spaces between the bristles of the bed during use of the cutting machine, which debris if left unremoved may hinder the efficient operation of the cutting tool and/or may impede air flow through the bed in the event the machine is the type in which a vacuum is applied to the bed during a cutting operation, and deals more particularly with such a cleaner capable of removing the debris from within the bristle bed using a comb and a vacuum combination to effect cleaning.
The work supporting bed used in sheet material cutting machine such as disclosed in U.S. Pat. No. 5,119,704, employs a means providing an upwardly facing flat supporting surface located in a horizontal plane for supporting sheet material to be cut. This means is an endless conveyor member trained over rotatable end units located at opposite ends of the frame of the machine so as to define an upper run of the belt defining the support surface and a belt lower run which defines the return run of the conveyor. The conveyor member in these machines may take many different forms, but is usually comprised of a number of slats extending transversely of the direction of conveyor movement and are linked to one another about hinge axes so as to form a continuous chain. Each slat carries a number of bristle blocks which when positioned in the upper run of the conveyor member have upwardly extending bristles terminating in a common plane to form the supporting surface. The bristles form a bed which is penetrable by a cutting knife, and in which bed may also be contained a vacuum pressure communicated to the supporting surface to aid in the holding and compressing of the material laid upon the support surface to be cut. The bristle units or squares are made of injection molded plastic with each unit having a lower base and a plurality of densely spaced bristles extending normally from the base. Depending on the material or machine application to be used, the bristles can take on varying heights depending on the type of application designated for the cutter. For a more complete description of the slat and the bristle bed assembly features, reference may be had to co-pending U.S. Application Ser. No. 08/124,803 entitled JOINTED BARRIER STRIP and filed on Sep. 21, 1993.
In the use of cutting machines having bristle beds of the aforementioned type, cutting debris tends to collect between the bristles of the bed and should be periodically removed to maintain efficient running of the machine. Debris which collects between bristles is the result of the cutting action of the reciprocating knife as its tip and part of its length is plunged below the support surface and within the densely spaced bristles extending normally from the base of each bristle block. Bristle bed cleaners have been used before, and one such type of cleaner is disclosed in U.S. Pat. No. 4,224,711. Here, an apparatus for cleaning a bristle structure to remove foreign material lodged in the bristles thereof is disclosed as comprising a means for cleaning a bristle structure by alternately accelerating the bristle structure to an elevated speed in one and an opposite direction generally parallel to the bristle extent. The problems associated with this type of cleaner is that cleaning must be achieved by separating the bristle block from the cutting machine, cleaning the block using the apparatus and thereafter reassembling the block to the machine after cleaning. This process is highly labor intensive and does not promote efficient use of time or labor.
The general object of the invention therefore is to provide a bristle bed cleaner to be used on a support surface comprised of a conveyor member wherein individual slats making up the conveyor member are capable of being cleaned so that the debris of fibers, cut cloth pieces and other foreign material lodged within the densely spaced bristles can be removed from within the bed without disassembling the bristle blocks from the holding slats, cleaning and thereafter reassembling the blocks with the involved holding slat.
It is yet a further object of the invention to provide a bristle bed cleaner assembly of the aforementioned type wherein the cleaner assembly is maintained at a predefined station at which individual slats of the conveyor member are indexed to thereby eliminate the need to move the cleaner assembly about the support surface except along a precribed cleaning path.
Still a further object of the invention is to provide a cleaner of the type having a comb-like implement and vacuum which is capable of using both mechanical and air pressure forces to clean foreign matter and other debris from within the bristle bed.